Detergent compositions

ABSTRACT

A detergent composition of the low temperature bleaching type comprises an inorganic persalt, for example sodium perborate, an inorganic peracid precursor, for example N,N,N&#39;&#39;,N-tetraacetyl ethylene diamine, a cotton substantive fluorescent agent of the 4,4&#39;&#39;-di(sym-triazinylamino)-stilbene-2,2&#39;&#39;-disulphonate type and not more than 0.001 per cent of a triazine derivative of specified formula. The compositions have a decreased tendency to discolor and form molodours during storage.

252-95. AU 1.65 EX uuucu ouuca I dlcul. 1 1 [11] 3,741,903 Evans June 26, 1973 [5 1 DETERGENT COMPOSITIONS 3,163,606 12/1964 Viveen et a1 252/95 X 3.177,l48 4/1965 Bright et ll. 252/95 X 1751 lnvcmor- 2,975,139 3/1951 Kauflmann et a1. 252/99 g England 3,519,579 7/1970 Blomeyer =1 11] 8/1 11 3,522,634 7 1970 Wood! [73] Ass1gnee: Lever Brothers Company, 252/95 New York, NY. 7 Primary Examiner-Mayer Weinblatt v [221 Med: 1971 Attorney- Louis F. Kline and Earl R. Ross [211 App]. No.: 206,143

Related 1.1.8. Application Data 57 ABSTRACT [63] Continuation-impart of Ser. No. 882,305, Dec- 4,

1959, abandoned, A detergent composition of the low temperature bleaching type comprises an inorganic persalt, for ex- 30 Foreign Anna/ion p i D g. ample sodium perborate, an inorganic peracid precur- Dec 12 1968 Great Britain 59 272/68 example thyme r amine, a cotton substantive fluorescent agent of the 4,- 52 us. c1 252/95 252/39 252/99 4Ksym-"iazinylammwilbene'z'z"disulphmate 260/248' type and not more than 0.001 per cent of a triazine de- 51 Int. Cl 01 M 7/52 rival spedfied The have a 58 Field of Search 252/95, 99, 89; decreased endmy dim! and storage.

[56] References Cited 9 Claims No Drawing UNITED STATES PATENTS 2,992,186 7/1961 Hellsten 252/99 X DETERGENT COMPOSITIONS This application is a continuation-in-part application of my copending application Ser. No. 882,305 filed Dec. 4, 1969 now abandoned.

This invention relates to fabric-washing detergent compositions, and in particular it relates to so-called low-temperature bleaching detergent compositions of the type functioning by the generation in aqueous solution during use of organic peracids, for example peracetic acid, perbenzoic acid or substituted perbenzoic acids.

Low-temperature bleaching detergent compositions essentially comprise inorganic persalts and organic compounds reactive at relatively low temperatures, for example 20 to 60 C, with the persalts, or with hydrogen peroxide liberated by the persalts, to form organic peracids. Hereinafter such organic compounds are referred to as organic peracid precursors."

For many years it has been common to incorporate inorganic persalts as bleaching ingredients in fabricwashing detergent compositions.

Some years ago, as is indicated in US. Pat. No. 3,163,606, it was discovered that the addition of an organic peracid precursor to a bleaching composition containing an inorganic persalt enhanced the bleaching action of the composition. Whereas inorganic persalts alone are only effective as bleaching agents in hot water, a mixture of an inorganic persalt and an organic peracid precursor can function effectively under cooler conditions and, therefore, it was hoped that the addition of an organic peracid precursor to an otherwise conventional detergent composition would produce a composition that would bleach fabric effectively when washing is conducted at low temperatures. In many countries, particularly those where heated washing machines are uncommon, fabric-washing is conducted at low temperatures and a conventional composition containing an inorganic persalt as the sole bleaching agent is relatively ineffective.

Therefore, organic peracid precursors were added to conventional detergent compositions of the type discussed above. However, it was noted that discoloration and mal-odor were produced in such compositions during storage. These compositions contained many other ingredients, but as there had been no serious instability problems with such compositions prior to the addition of the organic peracid precursor it was assumed that it was the organic precursor that was resulting in the poor storage propsrties. Attempts were made to improve the storage properties by altering the nature of the organic peracid precursors, but these attempts were unsuccessful and as a result it was not possible to produce commercially acceptable effective low-temperature bleaching detergent compositions. The public was, therefore, denied the advantages that such compositions would otherwise have provided.

It is an object of this invention to alleviate this problem.

By the present invention it has been discovered that the discoloration and mal-odor formation referred to above is connected with the use in low-temperature bleaching detergent compositions of various commercially-available fluorescent agents which are conventionally incorporated into fabric-washing detergent compositions. These fluorescent agents are derivatives of 4,4'-di(sym-triazinylamino)stilbene-2,2'-

disulphonic acid and salts thereof. in particular, it was found by the invention that these problems were caused by certain triazine derivatives present as impurities in the commercially-available fluorescent agents.

According to the present invention a detergent composition consists essentially of:

a. a detergent-active compound;

b. an inorganic persalt;

c. an organic peracid precursor susceptible to perhydrolysis;

d. at least one cotton-substantive fluorescent agent which is a derivative of 4,4'-di(symtriazinylamino)stilb'ene-2,2-disulphonic acid or of a salt thereof; and

e. not more than about 0.001 percent by weight of triazine derivatives having the structural formula:

wherein R, is a hydroxy group or a halogen atom,

R, is a hydroxy group or the group NR,R each of R, and R being a hydrogen atom, or an alkyl, substituted alkyl, aryl or substituted aryl group, or R and R, being combined in a heterocyclic ring, and

R is an alkyl, substituted alkyl, aryl or substituted aryl group.

The compounds of the formula (I) above wherein R is a hydroxy group are tautomeric and can exist in both the imidol (hydroxy) and amido (carbonyl) forms, but for convenience the imidol-form of structure and nomenclature is used in this specification.

Usually, R, is a hydroxy group or a chlorine atom.

Usually, R, is selected from the group consisting of hydroxy, dimethylamino, N-methylethylamino, monoethylamino, diethylamino, l-methyl-2- hydroxy)ethylamino, amilino, p-chloranilino and mor pholino groups.

Usually, R, is a methyl, phenyl or mono-sulphonated phenyl group.

The presence of the triazine derivatives having the formula (I) above is thought to cause the discoloration of, and the formation of foul odors in low-temperature bleaching detergent compositions by reaction with organic peracids formed during storage of the compositions.

The usual inorganic persalt is sodium perborate, which is used as the monohydratc or tetrahydrate, but other inorganic persalts, for example percarbonates, perpyrophosphates and persilicates may alternatively be used. These may not be true inorganic persalts in the strict chemical sense but they are believed to contain hydrogen peroxide of crystallization which is liberated in aqueous solution. The liberated hydrogen peroxide reacts with the organic peracid precursors to form the organic peracids.

The organic peracid precursors are typically compounds containing one or more acyl groups which are susceptible to perhydrolysis. Acetyl and benzoyl radicals are preferred, generating peracetic and perbenzoic acid, respectively. For commercial usage, the perhydrolysis should be sufficiently fast and the organic peracid precursor sufficiently watersoluble for the organic peracid to be formed in a reasonable time. Moreover, the perhydrolysis must predominate over the competing hydrolysis reaction and the organic peracid formed must be sufficiently stable for the desired bleaching to occur under the laundering conditions employed.

Specific organic peracid precursors which may be mentioned by way of example are esters such as sodium acetoxybenzene sulphonate and chloracetoxy salicylic acid, acyl-substituted cyanurates such as triacetylcyanurate, amides, particularly acetylated alkyl amines such as N,N,N',N-tetracetyl ethylenediamine, N-acyl azoles such as N-acetyl imidazole and N-benzoyl imidazole, acylated barbitones, hydantoins and glycolurils such as N,N'-diacetyl barbitone, N,N'-diacetyl-5,5- dimethylhydantoin and N,N,N,N'-tetracetyl glycoluril, respectively. Many other organic peracid precursors are known and are described in the literature, for example in British Pat. Nos. 836,988 and 855,735, the disclosures of which are included by reference herein.

The amounts of the inorganic persalt and the organic peracid precursor are both generally within the range of from about 5 to percent by weight in the detergent compositions. The ratio of the inorganic persalt to the organic peracid precursor can vary, depending on the number of reactive acyl radicals per molecule of the organic peracid precursor, but generally the amounts of the two components are of the same order.

The cotton-substantive fluorescent agents which are used in the low-temperature bleaching detergent compositions of the invention are well-known, and many such fluorescent agents are available commercially. Specific fluorescent agents which may be mentioned by way of example are:

a. 4,4'-di(2",4"-dianilinotriazin-6"-ylamino)- stilbene-2,2'-disulphonic acid and its salts,

b. 4,4'-di(2"-anilino-4"-morpholinotriazin-6"- ylamino)-stilbene-2,2'-disulphonic acid and its salts,

c. 4,4'-di(2"-anilino-4"-N- methylethanolaminotriazin-6"-ylamino)-stilbene-2,2'- disulphonic acid and its salts,

d. 4,4'-di(2"-anilino-4"-diethanolaminotriazin-6"- ylamino)-stilbene-2,2'-disulphonic acid and its salts,

e. 4,4-di(2"-anilino-4"-dimethylaminotriazin 6"- ylamino )-stilbene-2,2-disulphonic acid and its salts,

f. 4,4'-di(2"-anilino-4"-diethylaminotriazin-6"- ylamino)-sti1bene-2,2-disulphonic acid and its salts,

g. 4,4'-di(2"-anilino-4"-monoethanolaminotriazin' 6"-ylamino)-stilbene-2,2'-disulphonic acid and its salts,

h. 4,4'-di(2"-anilino-4"-(l-methyl-Z- hydroxy)ethylaminotriazin-6"-ylamino)-stilbene-2,2'- disulphonic acid and its salts,

i. 4,4'-di(2 "-methylamino-4"-p-chloroanilinotriazin- 6" ylamino)-stilbene-2,2'-disulphonic acid and its salts, and

j. 4,4'-di(2"-diethanolamine-4"-sulphanilinotriazin- 6"-ylamino)-stilbene-2,2disulphonic acid and its salts.

Usually these fluorescent agents are supplied and used in detergent compositions in the form of their alkali-metal salts, for example the sodium salts. in addition to these cotton-substantive fluorescent agents, detergent compositions may of course contain other types of fluorescent agent which may be either cotton or nylon-substantive, for example pyrazoline fluorescent agents. The total amount of fluorescent agent or agents used in a detergent composition is generally from about 0.1 to 2 percent by weight.

The triazine impurities are apparently formed during the preparation of the commercially-available fluorescent agents, and, if present in too high a concentration in the fluorescent agent, render the unpurified fluorescent agent unsatisfactory for use in a low-temperature bleaching detergent composition. A test for determining whether or not a fluorescent agent incorporates triazine impurities to an excessive extent is described be low.

Test for determining the presence of the undesirable triazine impurities in a fluorescent agent A detergent base powder had added to it 10 percent by weight of sodium perborate, 8 percent by weight of N,N,N,N'-tetraacetyl ethylenediamine and 2 percent by weight of the fluorescent agent. The ingredients are well mixed and then placed in a bottle which is put into an oven maintained at 60 C. The bottle is periodically examined for the color and odor of its contents. The development of a detectable discoloration or foul odor within a period of 24 hours indicates that the fluorescent agent used contains too high an amount of triazine impurities. An ideal detergent base powder for use in this test is described in Example 1 below.

If a fluorescent agent when tested as described above gives only a slight discoloration or foul odor by the end of the period of storage of the powder at 60 C, it may still be possible to use the fluorescent agent without purification in low-temperature bleaching detergent compositions of the present invention, but at a lower concentration than the 2 percent level used in the test. Thus, for example, a fluorescent agent used in a com position at the 2 percent level may include minor amounts of up to about 0.05 percent by weight of the triazine impurities, without the level of the impurities in the composition (ie 0.00l percent) being excessive. However, a fluorescent agent comprising, say, 0.2 percent by weight of the triazine impurities could only be used in a composition to an extent of about 0.5 percent by weight in order to avoid exceeding the same level of impurities in the composition. The maximum permitted concentration of the triazine impurities in the lowtemperature bleaching detergent compositions of the invention is about 0.001 percent by weight, as 1 have found that more than this amount of such impurities is unacceptable.

A method which may be used for the purification of a fluorescent agent containing an unacceptably high level of triazine impurities is described below. Method for the purification of a fluorescent agent A sample of the fluorescent agent is added to boiling water to which a minimum amount of ethanol is added in order to dissolve substantially all of the sample. The solution thus formed is cooled to about 60-65 C whereupon less soluble impurities in the fluorescent agent are precipitated and are removed from the solution by filtration. The filtrate is then cooled to room temperature to precipitate the fluorescent agent which is itself removed by filtration and subsequently dried. Other more soluble impurities in the fluorescent agent are left in the filtrate. Using this purification process it is possible in most cases to recover at least about percent by weight of the fluorescent agent incorporated in the original sample. Alternatively, chromatographic techniques may be used for the purification of the fluorescent agents, if desired.

After, as a result of the present invention, it was appreciated that the poor storage properties associated with low-temperature bleaching detergent compositions were caused vby some impurity present in the commercially-available fluorescent agents used in such compositions, rather than by the bleach precursors also used in such compositions, experiments were conducted to confirm this. Various commercially-available fluorescent agents were incorporated into lowtemperature bleaching detergent compositions, and the storage properties of the compositions were tested by the procedure described above. All were found to be unsatisfactory. Samples of the fluorescent agents were purified using the procedure described above. The impurities extracted from the fluorescent agents were found to contain large amounts of the triazine derivatives described above. When the purified fluorescent agents were used in low-temperature bleaching detergent compositions a marked improvement in the storage properties of the compositions were observed. The triazine derivatives were synthesized, and added to purifled samples of the fluorescent agents. When these adulterated fluorescent agents were used in lowtemperature bleaching detergent compositions, the originally-observed poor storage properties were encountered again. These findings conclusively showed that it is the triazine derivatives present in commercially-available fluorescent agents which are responsible for the poor storage properties associated with lowtemperature bleaching detergent compositions. Example 1 below gives typical findings which confirmed the invention.

It has been found that the triazine impurities are removed mainly in the first precipitate formed in the purification process, as tests conducted as described above on the first precipitate give strongly positive effects as regards the generation of color and foul odors, whereas no such effects are noted when the tests are repeated with the purified fluorescent agent and with the solids which may be separated from the final filtrate by evaporation. Examination of the first precipitate by mass-spectrographic and other analytical techniques shows the precipitate to comprise predominantly triazine derivatives having the structural formula (I), for example the compound 2,4-dianilino--hydroxytriazine when the fluorescent agent is an anilino substituted compound. Other triazine impurities which may be mentioned as causing discoloration and/or mal-odors are 2-anilinc-4,6-hydroxytriazine, 2-anilino-4- morpholino-6-hydroxytriazine, 2,4-di(ethylamino)-6- hydroxytriazine, and similar compounds containing halogen atoms, usually chlorine, instead of the hydroxy groups, to which they are readily hydrolyzed. Further compounds contain two triazine rings of formula (I) in which the groups R, are conjoined in a 4,4'-substituted stilbene-2,2'-disulphonic acid (or salt) group.

In order to improve the fabric bleaching effect, a detergent composition of the invention may advantageously incorporate one or more metallic catalysts which promote the organic peracid bleaching effect. Such metallic catalysts take the form of organic complexes with transition metals, such as cobalt, for example the cobalt chelates of pyridine 2-carboxylic acid and l,l0-phenan-throline. Any metallic catalyst used is normally present in very small amounts, and a level of a metallic catalyst in a detergent composition such that a concentration of the metallic catalyst in a wash liquor of about 1 to 5 X 10 mole per liter is generally satisfactory.

The stain removal performance of a detergent composition of the invention may also be improved by incorporating therein enzymes, which may be proteolytic or amylolytic in nature. The preferred enzymeis a'proteolytic enzyme (protease) obtained from b subrilis. In general, enzymes are incorporated into detergent com positions in amounts such that the detergent compositions have enzymic activities in the range of from 10 to 10 maltose units per kilogram, when amylolytic enzymes are used and from 5 to 20 Anson units per gram when proteolytic enzymes are used.

The combined use in a detergent composition of the invention of enzymes and the metallic catalysts mentioned above is particularly efficient.

A detergent composition of the invention will contain at least one detergent-active compound. The detergent-active content of the detergent composition will generally be from about 5 to about 30 percent, and preferably from about 10 to about 25 percent, by weight of the detergent composition. The nature of the detergent-active compound or compounds in the detergent composition is not an essential feature of the invention: any of the detergent-active compounds conventionally incorporated in or proposed for use in detergent compositions may be used, and those skilled in the art of formulating detergent compositions will be familiar with these detergent-active compounds and the various amounts and combinations in which they may advantageously be used. The detergent-active compound or compounds may be anionic, nonionic or amphoteric in character.

Typical anionic detergent-active compounds are water-soluble or water-dispersible salts of various organic acids. The cations of such salts are generally alkalimetals, such as sodium and, less preferably, potassium, but other cations, such as ammonium and substituted ammonium, can be used if desired. Examples of suitable organic acids are: alkyl benzene sulphonic acids, the alkyl chains of which contain from about eight to about 20 carbon atoms, such as p-dodecyl benzene sulphonic acid and linear alkyl (C benzene sulphonic acid; the mixtures of sulphonic acids obtained by reacting linear and branched olefins, particularly linear cracked-wax or Ziegler alpha-olefins, containing from about eight to about 22 carbon atoms, with sulphur trioxide; alkyl sulphonic acids obtained by reacting alkanes containing from about eight to about 22 carbon atoms with sulphur dioxide/oxygen or sulphur dioxide/chlorine (followed by hydrolysis in the latter case), or by the addition of bisulphite to olefins, particularly linear cracked-wax or Ziegler alpha-olefins, containing from about eight to about 22 carbon atoms; alkyl sulphuric acids obtained by reacting aliphatic alcohols containing from about eight to about 22 carbon atoms with sulphur trioxide; alkyl ether sulphuric acids, obtained by reacting molar quantities of aliphatic alcohols containing from about six to about 18 carbon atoms with from about 1 to about 15 moles of ethylene oxide, or a suitable mixture of ethylene oxide and propylene oxide, and subsequently reacting the alkoxylated alcohol with sulphur trioxide to yield the required acid; and natural or synthetic aliphatic carboxylic acids, particularly those derived from natural sources such as tallows, coconut oil, palm oil, palm kernel oil and groundnut oil.

Examples of suitable nonionic detergent-active compounds are: condensates of alkyl-phenols having an alkyl group (derived, for example, from polymerized propylene, diisobutylene, octene, dodecene or nonene) containing from about six to 12 carbon atoms in either a straight chain or branched chain configuration, with about to 25 moles of ethylene oxide per mole of alkylphenol; condensates containing from about 40 percent to about 80 percent polyoxyethylene by weight and having a molecular weight of from about 5,000 to about 11,000 resulting from the reaction of ethylene oxide with the reaction produce of ethylenediamine and excess propylene oxide; condensates of linear or branched-chain aliphatic alcohols containing from eight to 18 carbon atoms with ethylene oxide, eg a coconut alcohol-ethylene oxide condensate containing about 6 to 30 moles of ethylene oxide per mole of coconut alcohol; long-chain tertiary amine oxides corresponding to the general formula R,R,R -,N'O, wherein R, is an alkyl radical containing from about eight to 18 carbon atoms and R and R are each methyl, ethyl or hydroxy ethyl radicals, such as dimethyldodecylamine oxide, dimethyloctylamine oxide, dimethylhexadecylamine oxide and N-bis (hydroxyethyl) dodecylamine oxide; long-chain tertiary phosphine oxides corresponding to the general formula RR'R"P- O, wherein R is an alkyl, alkenyl or monohydroxyalkyl radical containing from 10 to 18 carbon atoms and R and R" are each alkyl or monohydroxyalkyl groups containing from one to three carbon atoms, such as dimethyldodecylphosphine oxide, dimethyltetradecylphosphine oxide, ethylmethyltetradecylphosphine oxide, dimethylstearylphosphine oxide, ethylpropylcetylphosphine oxide, diethyldodecylphosphine oxide, bis (hydroxymethyl) dodecylphosphine oxide, bis (Z-hydroxyethyl) dodecylphosphine oxide, 2-hydroxypropylmethyltetradecylphosphine oxide, dimethyloleylphosphine oxide and dimethyl-Z- hydroxydodecylphosphine oxide; and dialkyl sulphoxides corresponding to the general formula RRS*O, wherein R is an alkyl, alkenyl, betaor gammamonohydroxyalkyl radical or an alkyl or betaor gamma-monohydroxyalkyl radical containing one or two other oxygen atoms in the chain, the R groups containing from 10 to 18 carbon atoms and wherein R' is methyl, ethyl or alkylol radical, such as dodecyl methyl sulphoxide, tetradecyl methyl sulphoxide, 3- hydroxytridecyl methyl sulphoxide, Z-hydroxydodecyl methyl sulphoxide, 3-hydroxy-4-dodecyloxybutyl methyl sulphoxide, 2-hydroxy-3-decyloxypropyl methyl sulphoxide, dodecyl ethyl sulphoxide, 2- hydroxydodecyl ethyl sulphoxide and dodecyl-Z- hydroxyethyl sulphoxide.

Examples of suitable amphoteric detergent-active compounds are: derivatives of aliphatic secondary and tertiary amines, in which the aliphatic radical may be straight chain or branched and wherein one of the aliphatic substituents contains from about eight to 18 carbon atoms and one contains an anionic water solubilizing group, such as sodium-3-dodecylaminopropionate, sodium-3-dodecylaminopropanesulphonate and sodium N-2-hydroxydodecyl-N- methyl-taurate; and derivatives of aliphatic quaternary ammonium compounds, sulphonium compounds and phosphonium compounds in which the aliphatic radical may be straight chain or branched and wherein one of the aliphatic substitutents contains from about eight to 18 carbon atoms and one contains an anionic water solubilizing group, such as 3-(N,N-dimethyl-N-hexadecylammonium) propane-l-sulphonate betaine, 3-(N,N- dimethyl-N-hexadecyl-ammonium)-2-hydroxypropane-l-sulphonate betaine, 3-(dodecylmethylsulphonium) propane-l-sulphonate betaine, and 3-(cetylmethylphosphonium) ethane sulphonate betame.

Further examples of suitable detergentactive compounds commonly used in the art are given in 'Surface Active Agents, Volume I by Schwartz and Perry (lnterscience 1949) and Surface Active Agents, Volume II" by Schwartz, Perry and Berch (lnterscience 1958), the disclosures of which are included by reference herein.

Generally, a detergent composition of the invention will also include one or more detergency builders. Usually the total amount of detergency builders in a detergent composition of the invention will be from about 5 to about percent by weight of the detergent composition. Many detergency builders are known, and those skilled in the art of formulating fabric-washing detergent com ositions will be familiar with these materials. Examples of known detergency builders are sodium tripolyphosphate; sodium orthophosphate; sodium pyrophosphate; sodium trimetaphosphate; sodium ethanel-hydroxy-l,l-diphosphonate; sodium carbonate; sodium silicate; sodium citrate; sodium oxydiacetate; sodium nitrilotriacetate; sodium ethylenediaminetetraacetate; sodium salts of long-chain dicarboxylic acids, for instance straight chain (C to C succinic acids and malonic acids; sodium salts of alphasulphonated long-chain monocarboxylic acids; sodium salts of polycarboxylic acids; ie acids derived from the polymerization or copolymerization of unsaturated carboxylic acids and unsaturated carboxy acid anhydrides such as maleic acid, acrylic acid, itaconic acid, methacrylic acid, crotonic acid and aconitic acid, and the anhydrides of these acids, and also from the copolymerization of the above acids and anhydrides with minor amounts of other monomers, such as vinyl chloride, vinyl acetate, methyl methacrylate, methyl acrylate and styrene; and modified starches such as starches oxidized, for example using sodium hypochlorite, in which some anhydroglucose units have been opened to give dicarboxyl units.

Further, a detergent composition of the invention may contain any of the conventional detergent composition ingredients in any of the amounts in which such conventional ingredients are usually employed therein. Examples of these additional ingredients are lather boosters, such as coconut mono-ethanolamide and palm kernel monoethanolamide; lather controllers; inorganic salts such as sodium sulphate and magnesium sulphate; chlorine-releasing bleaching agents such as trichloroisocyanuric acid and sodium and potassium dichloroisocyanurates; antiredeposition agents, such as sodium carboxymethylcellulose; and, usually present only in minor amounts, perfumes, colorants, fluorescers, corrosion inhibitors and germicides.

A detergent composition of the invention can be prepared using any of the conventional manufacturing techniques commonly used or proposed for the preparation of detergent compositions, such as slurry-making followed by spray-drying or spray-cooling, and subsequent dry-dosing of sensitive ingredients not suitable for incorporation prior to the drying step. The inorganic persalts and organic peracid precursors, and enzymes and metallic chelate catalysts, are examples of such sensitive ingredients. Other conventional techniques, such as noodling, granulation, and mixing by fluidization in a fluidized bed, may be utilized as and when necessary. Such techniques are familiar to those skilled in the art of detergent composition manufacture.

By using such conventional manufacturing techniques, a detergent composition of the invention may be prepared in any of the common physical forms associated with detergent compositions, such as powders, flakes, granules, noodles, cakes, bars and, in some cases, liquids.

The invention is illustrated in the following Examples, wherein all parts and percentages are given by weight.

EXAMPLE I A commercially-available sample of the cotton fluorescent agent disodium 4,4-di(2"-anilino-4"- morpholinotriazin-6"-ylamino)-stilbene-2,2- disulphonate was added at a level of 2 percent to a lowtemperature bleaching detergent composition having the following formulation:

ingredient I: Sodium alltylbenzene sulphonate (prepared by the sulphonation 14 of DOB/055 alkylbenzene) Sodium toluene sulphonate 1 Coconut monoethanolamide 2 Alkaline sodium silicate l Sodium carboxymethylcellulose l0.$ Sodium sulphate 13 Sodium tripolyphosphate 35 Sodium perborate l0 N,N,N', N'-tetrsacetyl ethylenediamine 8 Water to l00 The powder was then placed in a sealed bottle and stored at 60 C. It was inspected at minute intervals for color and odor development. After 30 minutes the powder, which was initially white, had developed a pronounced yellow discoloration, and an objectionable odor was noticed when the bottle was opened. A quantity of the base powder, with no added fluorescent agent, was also subjected to this storage test, but remained unchanged throughout the duration of the test (2 hours).

A sample of the same commercially-available fluorescent agent was subjected to fractional crystallization from a water/ethanol mixture, and yielded three fractions:

a. a difficulty soluble material which precipitated rapidly;

b. the bulk of the fluorescent agent; and

c. a residue obtained by evaporating the filtrate to dryness.

A portion of each of these fractions was added at a level of 2 percent to the base detergent powder, and the detergent powders were then subjected to the same storage test already described. An untreated sample of the base detergent powder was used as a Control.

The detergent powder containing the material of fraction (a) exhibited the same changes on storage as had been previously observed, but the other three detergent powders remained completely unchanged. This N mum-r TNHQCH=CHQ V a 0mm oma ILlIiPh N NIL-r TNHPII Nlll'lr and the above analytical results suggested that the impurity (fraction (a)) was 2,4-dianilino-triazin-6-one (Ill):

0? l-ITHPh no-f l-Nurh Y NHPh (III) NHPh which has a molecular weight of 279 and a calculated elemental analysis of: C 64.5%, H 4.7%, N 25.1%. 2,4- dianilino-triazin-e-one may also exist in the enol form (IV).

A sample of 2,4-dianilino-triazin-6-one was synthesized as follows.

3 lg of aniline was slowly added to a stirred solution of cyanuric chloride l5g) in dry benzene (150 ml), the temperature being kept below 40 C. The mixture was stirred for a further 30 minutes, and then cooled and filtered. The residue was shaken with ml of water for 30 minutes to remove anilinium chloride, and afterwards was filtered, washed and dried. 3g of the residue was dissolved in I00 ml of dioxan, and treated with lg of potassium hydroxide in 3g of water. Sufficient water was then added to give a clear solution, which was then refluxed for two hours, acidified with acetic acid, and filtered while hot. The white precipitate collected was washed with ethanol, then washed with water, and finally recrystallized from dimethylformamide. The product gave identical infra-red and mass spectrometry results to those of the material of fraction (a).

When incorporated into a sample of the base detergent powder and subjected to the same storage conditions, the synthesized 2,4-dianilino-triazin-6-one produced the same deleterious storage properties, thus confirming the nature of the impurity present in the commercially-available fluorescent agent.

In order to dermine at what level this impurity starts .to cause storage problems which are unacceptable, various levels of the synthesized 2,4-dianilino-triazin- 6-one were added to samples of the base detergent powder, and the samples were subjected to the previously-described storage test. The following results were obtained:

Changes on storage at 60'C pronounced smell and discoloration, developing ra idly impurity level These results indicate that levels of the impurity up to 0.001 percent on the base detergent powder do not cause significant storage problems, and hence a lowtemperature bleaching detergent composition of the invention, which includes not more than this amount of such impurities, possesses acceptable storage properties. Above this level, the poor storage properties begin to become too serious to permit commercial utilization of the detergent compositions.

It should be appreciated that, even in a closed container wherein relative humidity is not a factor, storage at 60 C represents very severe conditions. These conditions were chosen deliberately to show up in a short space of time any inherent instability in the compositions under test. Therefore it follows that any composition which is unaffected by such conditions is highly stable and should remain unchanged for many months under normal storage conditions.

EXAMPLES 2 to 6 A detergent base powder was prepared by conventional slurry-making and spray-drying techniques. Proportions of sodium perborate and N,N,N',N'- tetraacetyl ethylenediamine were than added to the base powder to give a detergent powder having the following formulation:

lngredient Percentage Sodium alkyl benzene sulphonste re ared b sulphonation of ".2

/055 ai yl benzene) Sodium toluene sulphonate 1.0 Coconut ethanolamide 2.0 Alkaline sodium silicate 9.6 Sodium earboxymethyl cellulose 0.5 Sodium sulphate 12.6 Sodium tripolyphosphate 33.5 Sodium perborate l N.N,N',N'-tetraacetyl ethylenediamine 8 Water to l00 Samples of various commercially-available fluorescent agents were obtained and purified by the procedure described above. The fluorescent agents were incorporated in purified and unpurified form at a level of 2 percent in portions of the above base powder, giving five pairs of detergent powders.

The fluorescent agents used were as follows:

Fluorescent agent Disodium 4,4'-di( 2",4"-dianilino-triazin- 6"-ylamino)-stilbene-2.2'- disulphonate Example 6 Disodium 4,4'-di( 2"-anilino-4"- dicthylaminotriazin-6"- ylam|no)-stilbene-2,2'- disulphonate Each detergent powder was subjected to the storage test described under Example 1 above. initially each detergent powder was white and possessed only the smell associated with the base powder. The following results were obtained:

Example Changes on storage at C 2 (purified) None (unpurified Pink/smell within 20 minutes 3 (purified) None (unpurified) Very slight yellow/smell within 20 minutes 4 (purified) None (unpurified) Turned yellow in 20 minutes, and to pink in 50 minutes with a bad smell 5 (purified) None (unpurified) Turned green in 30 minutes with a bad smell 6 (purified) None (unpurified) Turned yellow in 35 minutes, and

to green with a bad smell EXAMPLES 7 and 8 Similar experiments to those described under Examples 2 to 6 were performed using sodium pacetoxybenzene sulphonate instead of N,N,N',N- tetraacetyl ethylenedlamine as the organic peracid precursor in the base detergent powder. The fluorescent agents used were:

Fluorescent agent rum 4,4'-di(2",4 "-dianilinotriszin- 6-ylamino)-stilbene-2,2'- disulphonste 8 Disodium 4,4'-di(2-anilino-4"- morpholinotriazin-6"- ylamino )-stilbene-2,2'- disulphonate Example The following results were obtained:

Example Chga'tggs observed on storage at 7 (purified) None (unpurified) ink/smell after a short time 8 (purified) one (unpurified) pink/smell aher a short time EXAMPLES 9 to 18 A quantity of the sodium salts of ten commerciallyavailable fluorescent agents were obtained, and a sample of each fluorescent agent was purified by the procedure described above. The purified and unpurified fluorescent agents were incorporated into a lowtemperature bleaching detergent composition having the following formulation:

4,4-di(2",4"-dianilinotriazin- 6' '-ylamino )-stilbene-2,2'- disulphonate Disodium 4,4'-di(2"-anilino4"- morpholinotriazin-6"- ylamino)-stilbene-2,2- disulphonate Disodium 4,4-di(2"-anilino-4' '-N methylethanclaminotriazin-6"- ylamino)-stilbene-2,2- disulphonate Disodium 4,4-di(2"'anilino-4"- diethanolam inotriazin-6"- ylamino )-stilbene-2,2'- disulphonate Disodium 4,4'-di( 2"-anilino-4' dimethylaminotriazin-6"- ylamino)-stilbene-2,2'- disulphonate Disodium 4,4'-di(2"-anilino-4"- diethylaminotriazin-6"- ylamino)-stilbene-2,2'- disulphonate Disodium 4,4'-di(2"-anilino-4"- monoethanolaminotriazin-6"- ylamino )-stilbene-2,2'- disulphonate Disodium 4,4'-di(2"-a.nllino-4"-( methyl- -hydroxy)ethylaminotriazin-6" glaminoystilbene-ZT- isulphonate Disodium 4,4'-di( 2' '-methylarnino-4"-pchloroanilinotriazin o ylamino )-stilbene-2,2- disulphonate Disodium 4,4-di(2"-diethanolamine-4' sulphanilinotriazin- 6' '-ylamino)-|tilbene-2,2- disulphonate Each Example consisted of a pair of detergent compositions containing the purified and unpurified fluorescent agent.

Samples of the compositions of Example 9, l0, l2, l4, l and 16 were stored in laminated packs at 37C]- 70% RH, and were examined at various intervals. The

changes observed are given in Table I below. Initially, 7

Table l Change observed in sample after:

3 weeks None Strong ellow/smell ale yellow Strong ellow/Imell ale yellow Yellow/smell Pale yellow Strong yellow/smell Pale yellow Example 5 weeks None Stron yellow/sine Pale gellow tron yellowllme Pale yellow Yellow/smell Pale gellow tron yellow/sme 1 week None None None Sli ht in lamcll one None None None None smell Stron yellow/ame Slight yellow None Strong yellow/smell None Slight yellow Pale yellow/slight 6 (unpurified) Slight Strong yellow/smell Stron pink/smell g yellow/smell Samples of the compositions of all the Examples were stored in laminated packs at 28C/70% RH, and inspected after three weeks. These conditions are examples of the most severe likely to be encountered during the normal storage. The results obtained are given in Table II below.

What is claimed is:

l. A detergent composition consisting essentially of:

a. a detergent-active compound selected from the group consisting of anionic, nonionic and amphoteric detergent-active compounds;

b. an inorganic persalt;

c. an organic peracid precursor susceptible to perh'ydrolysis;

d. at least one cotton-substantive fluorescent agent selected from the group consisting of:

i. 4,4'-di(2",4"-dianilinotriazin-6"-ylamino)- stilbene-2,2-disulphonic acid,

ii. 4,4-di(2"-anilino-4"-morpholinotriazin-6"- ylamino)-stilbene-2,2'-disulphonic acid,

iii. 4,4'-di(2"-amilino-4"-N- methylethanolaminotriazin-6"-ylamino)- stilbene-2,2'-disulphonic -anilinoiv. 4,4'-di(2"-anilino-4"-diethanolaminotriazin- 6"-ylamino)-stilbene-2,2'-disulphonic acid,

v. 4,4-di(2"-anilino-4"-dimethylaminotriazin-6"- ylamino)-stilbene-2,2-disulphonic acid,

vi. 4,4-di(2"anilino-4"-diethylaminotriazin-6"- ylamino)-stilbene-2,2'-disulphonic acid,

vii. 4,4'-di(2"-anilino-4"- monoethanolaminotriazin-- -p-chloroanilinotri-zin-6-ylamino)-stilbene- 2,2'-disulphonic acid,

viii. 4,4'-di(2"-anilino-4"-( l-methyl-2- hydroxy)ethylaminotriazin-6"-ylamino)- stilbene-2,2'-disulphonic acid,

chloroanilinotriazin-6"-ylamino)-stilbene-2,2'-

disulphonic acid, and

. 4,4'-di(2"-diethanolamine-4"- sulphanilinotriazin-6"-ylamino)-stilbene-2,2-

disulphonic acid, and alkali-metal salts of these sulphonic acids;

e. not more than about 0.001 percent by weight of triazine derivatives having the structural formula:

16 N,N,N,N-tetraacetyl ethylene diamine, N-acetyl imidazole, N-benzoyl imidazole, N,N'-diacetyl barbitone, N,N'-diacetyl-S,S-dimethylhydantoin and N,N,N',N- tetraacetyl glycoluril.

4. A detergent composition according to claim 1, wherein said detergent-active compound is from about 5 to about 30 percent by weight of said detergent composition.

5. A detergent composition according to claim 1, wherein said inorganic persalt is from about 5 to about 20 percent by weight of said detergent composition.

6. A detergent composition according to claim 1, wherein said organic peracid precursor is from about 5 to about 20 percent by weight of said detergent composition.

7. A detergent composition according to claim 1, wherein said fluorescent agent is from about 0.1 to about 2 percent by weight of said detergent composition.

8. A detergent composition according to claim 1, which additionally incorporates a cobalt chelate of 1,10-phenanthroline.

9. A detergent composition according to claim 1, which additionally incorporates a protease enzyme in an amount of from 5 to 20 Anson units per kilogram. i i l t 

2. A detergent composition according to claim 1, wherein said inorganic persalt is selected from the group consisting of sodium perborate, sodium percarbonate, sodium perpyrophosphate and sodium persilicate.
 3. A detergent composition according to claim 1, wherein said organic peracid precursor is selected from the group consisting of sodium acetoxybenzene sulphonate, chloracetoxy salicylic acid, triacetylcyanurate, N,N,N'',N'' -tetraacetyl ethylene diamine, N-acetyl imidazole, N-benzoyl imidazole, N,N''-diacetyl barbitone, N,N''-diacetyl-5,5-dimethylhydantoin and N,N,N'',N''-tetraacetyl glycoluril.
 4. A detergent composition according to claim 1, wherein said detergent-active compound is from about 5 to about 30 percent by weight of said detergent composition.
 5. A detergent composition according to claim 1, wherein said inorganic persalt is from about 5 to about 20 percent by weight of said detergent composition.
 6. A detergent composition according to claim 1, wherein said organic peracid precursor is from about 5 to about 20 percent by weight of said detergent composition.
 7. A detergent composition according to claim 1, wherein said fluorescent agent is from about 0.1 to about 2 percent by weight of said detergent composition.
 8. A detergent composition according to claim 1, which additionally incorporates a cobalt chelate of 1,10-phenanthroline.
 9. A detergent composition according to claim 1, which additionally incorporates a protease enzyme in an amount of from 5 to 20 Anson units per kilogram. 